See also Tocantins River on Wikipedia, and the disclaimer.
To'cantins' River, 1,000 miles long, from the junction of the Almas and Maranhão to the Para, into which it falls. Its branches are the Araguaya, Paraman, Great Somno, Tucahunas and Theresa. The Tocantins is eight miles wide at its mouth, and the tide ascends the river for 300 miles.